Infrastructure Security Architect

Infrastructure Security Architect (Contract – Outside IR35) 

• Clearance: Active DV + Active NPPV3 (both required)
• Job Title: Infrastructure Security Architect
• Contract: Outside IR35
• Location: UK (hybrid/remote depending on site access)
• Start: ASAP (subject to clearance verification)
• Rate: Competitive (DOE)

Overview:

We are looking for a highly experienced Security Architect with a strong Infrastructure Architecture background to support the design, assurance and delivery of secure platforms in a high-assurance environment. This role suits someone who can operate across enterprise infrastructure, networks, hosting platforms, identity, endpoint, and cloud, producing clear architecture artefacts and driving security-by-design through engineering teams.

You will be working across complex estates (legacy + modern) and supporting secure transformation, ensuring infrastructure designs align to relevant UK security standards and governance.

Key Responsibilities (Security + Infrastructure Architecture):

• Own and deliver security architecture for infrastructure solutions covering:
  • Data centres / hosting platforms, virtualisation, storage, backup, DR, and platform services
  • Network architecture (segmentation, routing, firewalls, proxies, secure remote access)
  • Identity & access architecture (AD, Azure AD/Entra ID, federation, PAM)
  • Endpoint / server hardening (Windows/Linux baselines, configuration management, patching)
  • Cloud and hybrid connectivity and security patterns (where applicable)
• Produce high-quality architecture documentation, including:
  • HLD/LLD, security design packs, reference architectures, patterns/standards, and roadmaps
  • Security requirements, control mappings, and architecture decision records
• Lead threat modelling and risk assessments on infrastructure designs; define mitigations and proportionate controls.
• Drive secure-by-design outcomes: work with infrastructure engineers, network teams, platform teams and vendors to implement secure architectures.
• Provide assurance through governance forums (design authorities / architecture review boards), ensuring designs are supportable, compliant, and operationally viable.
• Define and assure controls for:
  • Network segmentation / zero trust principles
  • Encryption in transit/at rest, key management, certificate services/PKI
  • Secure administration models (jump hosts/bastions, privileged access workflows)
  • Logging/monitoring/SIEM integration and security observability
• Support operational security posture: contribute to hardening standards, vulnerability management approaches, secure build pipelines, and incident learnings.

Essential Skills & Experience:

• Demonstrable experience as a Security Architect with deep Infrastructure Architecture capability.
• Comfortable producing “client-ready” architecture artefacts and presenting them to senior technical and non-technical stakeholders.
• Strong knowledge of UK security frameworks and standards such as:
  • NCSC guidance, HMG Security Policy Framework (SPF), secure architecture principles
  • ISO 27001/27002, NIST, CIS (where appropriate)
• Strong grasp of security controls and how they apply to infrastructure (network, compute, identity, endpoint).
• Ability to balance security, operability, performance and cost in design decisions.

Desirable:

• Experience supporting assurance/accreditation style activity (e.g., control mapping, risk treatment approaches).
• Knowledge of DevSecOps / secure automation (IaC concepts, CI/CD security controls).
• Prior work in highly sensitive environments with strict governance, auditability, and separation-of-duties requirements.